The present invention relates to an electronic apparatus having an interface section capable of supplying power to and transmitting information with external equipment connected externally.
Conventionally, in electronic apparatuses capable of connecting externally to a plurality of external equipments, there are multiple interface sections capable of supplying power to and transmitting information with external equipment connected externally via cables such as USB cables. It is possible for each of these external equipments connected externally to supply an established amount of power such as 2.5 W. In a case where it is necessary during the execution of the performance of the electronic apparatus, the external equipments are made to perform and the performance demanded via such a local network as a LAN from a computer such as the host PC is executed in accordance with the operation of the user. In a recording apparatus capable of recording image information stored in external equipment and having, for example, a USB interface and a memory card interface as the interface connectable to the external equipment, the connected conditions of the external equipments connected to these USB and memory card interfaces are detected. When it is detected that the external equipments are connected to both of these two types of interfaces, a judgment is made as to whether the total electrical energy demanded by these external equipments exceeds the maximum value of electrical energy to be supplied to the external equipments by the recording apparatus. If the total energy exceeds the maximum value, the external equipments are selected in accordance with the performance condition of the previously connected external equipments, and power is then supplied (see generally, Japanese Application Publication JA2004-284173 (pgs. 1-12, FIG. 4)).
In the aforementioned conventional electronic apparatus, however, in a case where a plurality of external equipments is connected by an interface section, it is necessary to ensure a large amount of power in order to supply the required power for each of the multiple external equipments. For example, in order to supply 2.5 W of power for each of four external equipments, it is necessary to ensure 10 W of power. For this reason, the total amount of energy supplied is greatly increased when many external equipments are connected and, in a case where power necessary for the performance of the electronic apparatus itself is a small amount rather than a large amount, the electronic apparatus is made larger and the cost is greatly increased with the goal of ensuring a greater power supply.
Also, in the recording apparatus according to the aforementioned Japanese Patent Application to prevent this type of increase in the supply of power, external equipments are selected in accordance with the performance condition of the previously connected external equipments, and power is then supplied, but, in this recording apparatus, regardless of desire to use the externally connected external equipments there are instances where power is not supplied to the appropriate external equipment to render the equipment useless.
The present invention is made in consideration of these problems, it is an objective to provide an electronic apparatus capable of efficiently selecting and supplying power to external equipments in accordance with the analyzed process performance of the electronic apparatus and the type of externally connected external equipments.